Painting injection study using a virtual accelerator in a high-intensity proton accelerator

Harada, Hiroyuki

no journal, , 

The J-PARC 3-GeV RCS injects proton beams with stripping electrons of H ion beams by a stripper foil. This injection scheme makes it possible to have multi-turn injections in same phase space of ring. However, beam loss caused by foil scattering of circulating beam are concerned. In addition, enhance of beam loss source caused by space charge effect is concerned in a high intensity operation. Therefore, suppression of foil hits and mitigation of space charge force are essential issues to realize a high intense beam operation. The RCS adopts a painting injection. The painting injection fills the elliptical phase-space at the injection point with the injection beam by changing the injection and ring orbits during multi-turn beam injection. In my work, the designed painting injection was established by using a virtual accelerator developed on a computer. The results leads to high intensity output and low beam loss in the RCS. In this presentation, the RCS and painting injection scheme are introduced and a lot of beam tuning results are reported.